Rotary mud



L. S. COPELIN.

ROTARY MUD.

APPLiCATION FILED AUG.5 1921.

Patented Mm. 28, 1922'.

LEONARD S. COPELIN, OF SEALBEACH, CALIFORNIA.

ROTARY MUD.

ame-e.

To all whom it may concern:

Be it known that LEONARD S. CorELIN, a citizen of the United States of America, residing at Seal Beach, in the county of Orange and State of California, has invented newand useful Improvements in R0- tary Muds, of which the following is a specification. C

The object of the invention is to provide an efficient and comparatively inexpensive material for and method of sealing driven or drilled wells for oil, gas and the-like in strata which is of crumbling or loose formatlon or has a tendency to cave, as a means. of

as a rotary mud, of

ily afiected by oil or deposited in small difficult of detection, permeable from .tary mud or sealin maintaining an unobstructed passage and of excluding or preventing the inflow to the well or hole of undesirable liquids or other products tending to contaminate the product for Which the well is designed and for which purpose it has been the practice to use a mud, referred to in the art a clay consistency which is objectionable by reason of being, difficult to handle or apply, of being readother liquid products of the well, of absorbing oil which when quantities is rendered which is more or less the outside by liquids or gases which it may be the desire to exclude and the like; and therefore it is the particular object of the invention to provide a rog material which by reason ofrbeing of a radically different specific gravity from that of soil, sand, rock, drillings and the like is readily distinguishable and separable therefrom by precipitation of the latter, which has the property of being readily applied to the portions of the-walls of the hole or well which are to be sealed, which is of a cohesive property and a colloidal texture adapting it to form not only a wall adhesive but an aggregative of the loose particles of soil and rock incidental to a caving condition, whichfis repellent to oil and practically impermeable by water and similar liquids. v

In the drawings, in which the means for carrying out themethod is conventionally illustrated, Figure 1 is a view partly in ele vation and partly in section of a conventional well boring apparatus; and F igure 2 is a sectional view of the walls of a well hole illustrating the solidifying effect of the use of a rotary mud. i

Specification of Letters Patent.

Patented Mar. 28, 19 22,

Application filed August 5, 1921. Serial No. 490,170.

The usual drill bit 1 is employed and carried at the lower extremity of the tubular drill 'rod,2, the latter being surrounded by the tubularcasing 3 that is lowered behind the drill bit and forms the well tube when the oil or gas area has been reached. If the hole or shaft being drilled shows a caving tendency the rotary mud is introduced through the drill rod 2, entering the hole in the vicinity of the bit 1 and being a calcium carbonate preferably in the form' of, waste. or refuse lime which is a by-product of the manufacture of sugar, is applied to the walls of the well by the operation of the drill, filling the interstices of the wall and serving as a binder for loose particles of soil and rock. This particular material isof special advantage in this connection; first, because, being of a less specific gravity than rock and rock filings or cuttings, the particles of the latter readily separate and precipitate; second, because the said material is of a cohesive nature and colloidal texture adapting it to penetrate the interstices or pores of the rock and soil and forms a plaster which keys itself to the material and at the same time anchors the loose particles thereof; and third, because the said material is not only repellent to oil but is impermeable to water except to a very slight degree and constitutes a barrier to exclude moisture and liquids in strata which are productive of undesirable materials tending to contaminate the product for which the well is designed.

In Figure 2, at 4:, there'is shown the effect of the use of the rotary mud :in the manner above described. I

The lime mud has not the property of setting or becoming hard but remains permanently plastic and constitutes a permanent barrier which is not readily attacked by liquids in the excluded strata. The mud is removed from the exposed strata by the ordinary washing method.

The objection to clay and like rotary muds, in addition to the unsubstantial char-c acteristics thereof is that they are readily. absorptive of oil so that if the operation involves prospecting for oil, and the latter appear in very small quantities, the-tests may fail to show any trace thereof if a re: tary mud of the ordinary type is employed, whereas with the rotary mud of calcium carbonate the oil will appear in small globules in the samples withdrawn ordinarily at in tervals from the hole as the drilling proceeds, and therefore constitutes a safe and reliable guide to the driller as to the ultimate yield of the well.

In applying the lime as a rotary mud a further advantage resides in the fact that it is at first readily absorptive of water to form a thick plastic mass which can readily be worked by the drill in forming a coating of cement to anchor loose and caving portions of the wall of the hole.

Having described the invention, what is claimed as new and useful is 1. The method of solidifying soil in wells and other shafts which consists in the injection of a calcium carbonate in the interstices of caving or loose portions.

2. The method of solidifying soil in wells and other shafts which comprises the application .of waste or refuse lime to caving or loose portions of the walls.

3. The method of solidifying soil in wells and other shafts which comprises the applicatio'rr-to caving or loose portions of the walls thereof of waste or refuse lime constituting a by-product of the manufacture of sugar.

4. The method of solidifying soil in wells and other shafts showing a caving tendency which consists in introducing into the well or shaft waste or refuse lime which is a byproduct of the manufacture of sugar, an

thereafter applying the same to the walls by operation of the drill to fill the interstices of the wall and serve as a binder for loose particles of soil in'rock.

In testimony whereof he aflixes his signature.

LEONARD S. COPELIN. 

